Abstract: Background: Sentinel lymph node biopsy (SLNB) plays a crucial role in the management of patients with malignant melanoma. However, limited studies have been conducted in SLNB for lower extremity malignant melanoma in Asians.
Objectives: We used coaxial projective lymphography to demonstrate a technique for SLNB in lower extremity malignant melanoma and evaluated the accuracy and efficacy of this new technique.
Methods: Twenty patients with lower extremity malignant melanoma who underwent SLNB were enrolled in this prospective study. All the patients had SLNB performed under the guidance of Indocyanine Green (ICG) based coaxial projective lymphography. Tissue samples of suspicious lymph nodes with or without ICG labeling were excised, and analyzed by intraoperative frozen section examination and pathological examination. The SLNs were identified by coaxial projective lymphography before and after skin incision and the localization accuracy was compared with that based on the surgeons’ experience.
Results: The accuracy of locating SLNs with ICG-based coaxial projective lymphography was 95 % (n = 19) before skin incision and 100 % (n = 20) after skin incision. All 20 ICG-labeled tissues contained SLNs, and a total of 46 SLNs were detected. The surgeons empirically identified 65 % (n = 13) of lymph nodes after skin incision. The coaxial projective lymphography detection rate of lymph nodes was significantly higher than that of surgeons based on their experience.
Conclusions: ICG-based coaxial projective lymphography can accurately localize SLNs on the inguinal surface of patients with lower extremity malignant melanoma. It provides an alternative solution for SLNB in lower extremity malignant melanoma when 99mTc cannot be used to locate SLNs preoperatively.
Keywords: Indocyanine green, Coaxial projective lymphography, Sentinel lymph node biopsy, Malignant melanoma